1. Field of the Invention
The present invention relates to a poly(ethylene 2,6-naphthalate) film which has excellent runnability, abrasion resistance and strength.
2. Description of Related Art
Recently, a small thickness and high strength of a base film are increasingly required, because of a long recording time and a small size of a video tape and an increased capacity of a capacitor. It is difficult to satisfy sufficiently these requirements, when a conventional poly(ethylene terephthalate) film is used as the base film. A poly(ethylene 2,6-naphthalate) film which is stretched in machine and transverse directions at nigh drawing ratios has developed as a substitute for the poly(ethylene terephthalate) film. The poly(ethylene 2,6-naphthalate) film has excellent strength, but fine particles contained in the film easily drop off from a film surface because of high draw ratios in machine and transverse directions. The generation of abrasion powder due to dropped particles causes a fault, namely a drop out in the magnetic recording application, and undesirably decreased dielectric strength in the capacitor application.